14 & possibly pregnant? please give me your opinion...

i think i'm pregnant, im 14. i had unprotected sex june 6th, then almost 1 week later i started spotting, and then almost 2 weeks later i got some bleeding for 3 days, but it was really light, then really heavy, then really light again & that happened for june & july, now its late august and i still haven't gotten my period but since i had sex i've gained weight,but just in my stomach area; not sure if its just bloating or something, been nausous alot, moody, really tired but cant sleep at night, i've had headaches and sore throats, i've been constantly hungry, and peeing alot more then usual, and i've had these like stomach cramps that were lower in my stomach but they went away when i either laid down or went to the bathroom. all the urine tests i've taken have been negative,& ive been having almost this constant like white sticky discharge...its weird but im still unsure... can someone please give me advice or their opinion on if they think im pregnant?